Pond Evaporation Calculation													1/31/17
Weather Station Data provided by Northern Colorado Water Conservancy District
See Weather Station Location Map at:
http://www.northernwater.org/WaterConservation/WeatherandETData.aspx
Notes:
Current month reflects values through "Reference Date".
Pond Evap. calculated per recent Division 1 Water Court decree language:							Lower South Platte Home Page
Gross Pond = .84(Alfalfa ETr)							Pond Evaporation Reports Main Menu
Net Pond = .84(Alfalfa ETr) - .7(Total Precip)
Alfalfa reference ETr computed by Standard ASCE equation from daily weather data.
Winter pond evap. is a reference for unfrozen ponds.
For Growing Degree Days:
Tmax = 86° F, Tmin = 50° F and Tbase = 50° F
														Totals
Weather Station	2016	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	or Avg.
Ovid	Avg. Temp ° F	26.58	35.16	42.47	48.62	55.71	73.8	74.59	70.25	62.91	54.06	41.31	24.21	50.81
Ref date as of 12/31/2016	Total Precip "	0.3	0.82	1.41	4.06	2.89	3.27	2.87	0.87	0.42	0.91	0.28	0.3	18.4
Site Type: Alfalfa	Total Alfalfa ETr "	1.43	3.1	5.63	5.77	6.7	10.73	9.71	7.71	6.28	5.04	3.12	1.93	67.15
Total Growing Degee Days from March 1		0	0	177	199	300	642	695	601	462	364	169	11	3620
Gross Pond Evap	Total "	1.2	2.6	4.73	4.85	5.63	9.01	8.16	6.48	5.28	4.23	2.62	1.62	56.41
Net Pond Evap	Total "	0.99	2.03	3.74	2	3.61	6.72	6.15	5.87	4.98	3.6	2.42	1.41	43.52
Crook	Avg. Temp ° F	26.1	35.99	42.85	48.83	55.55	72.66	74.02	69.52	62.71	53.61	40.61	23.56	50.5
Ref date as of 12/31/2016	Total Precip "	0.29	0.47	0.82	2.8	2.07	1.36	2.16	0.39	0.66	0.72	0.19	0.36	12.29
Site Type: Alfalfa	Total Alfalfa ETr "	1.47	3.28	5.8	5.87	6.58	9.66	9.15	7.54	6.14	4.91	3.16	1.89	65.45
Total Growing Degee Days from March 1		0	0	182	207	299	614	684	573	470	377	178	17	3601
Gross Pond Evap	Inch	1.23	2.76	4.87	4.93	5.53	8.11	7.69	6.33	5.16	4.12	2.65	1.59	54.97
Net Pond Evap	Inch	1.03	2.43	4.3	2.97	4.08	7.16	6.17	6.06	4.7	3.62	2.52	1.34	46.38
Sterling	Avg. Temp ° F	25.36	35.39	42.67	48.87	55.59	72.72	74.02	69.78	62.95	53.68	40.66	23.24	50.41
Ref date as of 12/31/2016	Total Precip "	0.22	0.53	0.63	3.29	2.62	1.41	1.67	0.53	0.95	0.43	0.35	0.43	13.06
Site Type: Alfalfa	Total Alfalfa ETr "	1.4	3.18	5.51	5.8	6.45	9.69	9.15	7.74	6.18	4.78	2.98	1.57	64.43
Total Growing Degee Days from March 1		0	0	174	205	301	616	679	584	472	375	185	13	3604
Gross Pond Evap	Inch	1.18	2.67	4.63	4.87	5.42	8.14	7.69	6.5	5.19	4.02	2.5	1.32	54.13
Net Pond Evap	Inch	1.02	2.3	4.19	2.57	3.58	7.15	6.52	6.13	4.53	3.71	2.26	1.02	44.98
Brush	Avg. Temp ° F	24.32	33.94	42.14	48.27	55.55	71.39	72.88	68.42	62.3	53.25	40.21	21.33	49.5
Ref date as of 12/31/2016	Total Precip "	0.28	1.16	1.79	3.51	3.23	1.33	3	1.5	0.68	0.54	0.3	0.74	18.06
Site Type: Alfalfa	Total Alfalfa ETr "	1.31	3.02	5.45	5.84	6.69	9.08	9.18	7.54	6.2	5.01	3.15	1.37	63.84
Total Growing Degee Days from March 1		0	0	173	218	324	593	668	573	471	398	196	10	3624
Gross Pond Evap	Inch	1.1	2.54	4.58	4.91	5.62	7.63	7.71	6.33	5.21	4.21	2.65	1.15	53.64
Net Pond Evap	Inch	0.9	1.72	3.33	2.45	3.36	6.7	5.61	5.28	4.73	3.83	2.44	0.63	40.98
Fort Morgan	Avg. Temp ° F	24.43	34.18	42.05	48.54	55.76	72.09	73.76	69.49	63.45	54.51	41.79	22.68	50.23
Ref date as of 12/31/2016	Total Precip "	0.16	0.48	2.4	3.46	3.44	2	5.63	2.46	1.8	0.67	0.62	0.67	23.79
Site Type: Turf	Total Alfalfa ETr "	1.28	2.68	4.54	5.18	6.35	8.66	8.61	7.21	5.71	4.29	2.69	1.16	58.36
Total Growing Degee Days from March 1		0	0	159	209	314	604	682	595	492	392	183	10	3640
Gross Pond Evap	Inch	1.08	2.25	3.81	4.35	5.33	7.27	7.23	6.06	4.8	3.6	2.26	0.97	49.01
Net Pond Evap	Inch	0.96	1.92	2.13	1.93	2.93	5.87	3.29	4.33	3.54	3.13	1.83	0.51	32.37
Wiggins	Avg. Temp ° F	22.72	33.71	41.64	48.13	54.93	71.44	72.78	68.87	62.5	53.41	40.56	21.65	49.36
Ref date as of 12/31/2016	Total Precip "	0.24	0.35	0.98	2.73	3.3	1.23	1.9	1.31	0.13	0.68	0.7	0.62	14.17
Site Type: Alfalfa	Total Alfalfa ETr "	1.25	3.03	5.13	5.76	6.27	9.27	9.78	8.53	6.46	5.01	3.17	1.26	64.92
Total Growing Degee Days from March 1		0	0	157	212	302	590	656	576	472	373	178	6	3522
Gross Pond Evap	Inch	1.05	2.55	4.31	4.84	5.27	7.79	8.22	7.17	5.43	4.21	2.66	1.06	54.56
Net Pond Evap	Inch	0.88	2.3	3.62	2.93	2.96	6.93	6.89	6.25	5.34	3.73	2.17	0.62	44.62
Fort Collins East	Avg. Temp ° F	27.64	36.01	41.21	47.03	52.61	69.94	71.68	67.07	61.5	53.23	42.02	24.51	49.54
Ref date as of 12/31/2016	Total Precip "	0.42	0.64	1.38	2.08	1.9	0.17	0.19	0.51	0.13	0.34	0.28	0.4	8.44
Site Type: Alfalfa	Total Alfalfa ETr "	1.83	3.47	4.81	5.35	6.02	9.34	9.16	7.93	5.83	5.12	3.38	1.51	63.75
Total Growing Degee Days from March 1		0	0	124	178	257	561	630	535	439	341	172	10	3247
Gross Pond Evap	Inch	1.54	2.91	4.04	4.49	5.06	7.85	7.69	6.66	4.9	4.3	2.84	1.27	53.55
Net Pond Evap	Inch	1.24	2.47	3.07	3.04	3.73	7.73	7.56	6.3	4.81	4.06	2.64	0.99	47.64
Eaton	Avg. Temp ° F	25.54	35.2	40.79	47.51	53.7	70.66	71.83	66.97	61.37	52.3	40.54	22.43	49.07
Ref date as of 12/31/2016	Total Precip "	0.51	0.53	1.65	2.51	2.99	1.3	0.49	0.77	0.43	0.83	0.36	0.65	13.02
Site Type: Alfalfa	Total Alfalfa ETr "	1.57	3.35	4.95	5.65	6.44	9.39	8.74	7.31	5.53	4.46	3.06	1.24	61.69
Total Growing Degee Days from March 1		0	0	129	201	284	570	642	545	443	335	166	2	3317
Gross Pond Evap	Inch	1.32	2.81	4.16	4.75	5.41	7.89	7.34	6.14	4.65	3.75	2.57	1.04	51.83
Net Pond Evap	Inch	0.96	2.44	3	2.99	3.32	6.98	7	5.6	4.34	3.17	2.32	0.59	42.71
Johnsons Corner	Avg. Temp ° F	26.94	35.5	41.16	47.46	53.35	70.65	73.33	68.44	63.23	54.72	43.27	24.78	50.24
Ref date as of 12/31/2016	Total Precip "	0.74	0.89	1.75	2.04	2.51	0.34	1.47	0.39	0.24	0.69	0.33	0.54	11.93
Site Type: Alfalfa	Total Alfalfa ETr "	1.55	3.22	4.52	5.2	5.87	9.17	9.87	8	6.1	5.06	3.18	1.47	63.21
Total Growing Degee Days from March 1		0	0	115	185	258	573	668	559	460	352	175	14	3359
Gross Pond Evap	Inch	1.3	2.7	3.8	4.37	4.93	7.7	8.29	6.72	5.12	4.25	2.67	1.23	53.08
Net Pond Evap	Inch	0.78	2.08	2.57	2.94	3.17	7.46	7.26	6.45	4.96	3.77	2.44	0.86	44.74
Gilcrest	Avg. Temp ° F	23.55	34.04	41.51	48.03	54.65	72.8	74.72	68.06	61.61	52.22	40.1	21.29	49.38
Ref date as of 12/31/2016	Total Precip "	0.49	0.52	0.82	2.75	2.35	1.2	2.25	1.67	0.8	0.7	0.33	0.4	14.28
Site Type: Alfalfa	Total Alfalfa ETr "	1.3	3	4.56	5.43	6.26	9.47	9.27	7.36	5.53	4.46	2.67	1.25	60.56
Total Growing Degee Days from March 1		0	0	142	210	290	612	684	565	451	346	168	4	3472
Gross Pond Evap	Inch	1.09	2.52	3.83	4.56	5.26	7.95	7.79	6.18	4.65	3.75	2.24	1.05	50.87
Net Pond Evap	Inch	0.75	2.16	3.26	2.64	3.61	7.11	6.21	5.01	4.09	3.26	2.01	0.77	40.88
Longmont South	Avg. Temp ° F	28.81	37.85	41.53	48.35	54.08	70.93	73.45	68.02	62.33	55.54	43.64	27.14	50.97
Ref date as of 12/31/2016	Total Precip "	0.48	0.77	1.63	2.18	1.3	0.99	0.8	0.72	0.4	0.44	0.31	0.57	10.59
Site Type: Alfalfa	Total Alfalfa ETr "	1.78	3.69	4.39	5.37	5.76	8.87	9.44	7.41	5.75	5.58	3.04	1.85	62.93
Total Growing Degee Days from March 1		0	0	118	188	270	567	651	542	437	358	180	33	3344
Gross Pond Evap	Inch	1.5	3.1	3.69	4.51	4.84	7.45	7.93	6.22	4.83	4.69	2.55	1.55	52.86
Net Pond Evap	Inch	1.16	2.56	2.55	2.98	3.93	6.76	7.37	5.72	4.55	4.38	2.34	1.16	45.46
Fort Collins NW	Avg. Temp ° F	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Ref date as of 12/31/2010	Total Precip "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Site Type: Turf	Total Alfalfa ETr "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Total Growing Degee Days from March 1		0	0	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Gross Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Net Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Fort Collins Central	Avg. Temp ° F	28.02	35.78	42.08	48.98	54.72	71.12	73.23	67.88	61.83	52.62	41.98	25.18	50.29
Ref date as of 12/31/2016	Total Precip "	0.62	0.21	1.37	2.56	1.88	0.15	1.09	0.7	0.21	0.4	0.29	0.29	9.77
Site Type: Turf	Total Alfalfa ETr "	1.68	3.01	3.96	4.76	5.48	7.47	7.72	6.44	4.74	3.68	2.45	1.24	52.63
Total Growing Degee Days from March 1		0	0	129	201	290	574	656	546	445	341	173	9	3364
Gross Pond Evap	Inch	1.41	2.53	3.33	4	4.6	6.27	6.48	5.41	3.98	3.09	2.06	1.04	44.2
Net Pond Evap	Inch	0.98	2.38	2.37	2.21	3.29	6.17	5.72	4.92	3.83	2.81	1.86	0.84	37.38
Windsor	Avg. Temp ° F	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Ref date as of 7/1/2012	Total Precip "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Site Type: Dryland Pasture	Total Alfalfa ETr "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Total Growing Degee Days from March 1		0	0	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Gross Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Net Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Greeley West	Avg. Temp ° F	25.73	35.11	41.48	48.1	54.75	71.8	74.15	68.98	63.22	53.85	41.93	22.84	50.16
Ref date as of 12/31/2016	Total Precip "	0.62	0.64	1.12	2.56	2.31	1.53	0.97	1.26	0.27	0.79	0.36	0.78	13.21
Site Type: Turf	Total Alfalfa ETr "	1.36	2.83	4.3	4.97	6.07	8.37	8.25	6.83	5.16	3.95	2.52	1.17	55.78
Total Growing Degee Days from March 1		0	0	135	219	296	606	684	584	474	361	176	8	3543
Gross Pond Evap	Inch	1.14	2.38	3.61	4.17	5.1	7.03	6.93	5.74	4.33	3.32	2.12	0.98	46.85
Net Pond Evap	Inch	0.71	1.93	2.83	2.38	3.48	5.96	6.25	4.86	4.15	2.77	1.86	0.44	37.62
Loveland	Avg. Temp ° F	28.68	36.75	41.89	48.67	55.05	71.8	74.39	69.31	63.91	55.53	43.79	26.9	51.39
Ref date as of 12/31/2016	Total Precip "	0.46	0.42	1.5	1.82	2.04	0.42	0.88	0.4	0.27	0.4	0.21	0.39	9.21
Site Type: Turf	Total Alfalfa ETr "	1.67	3.01	4.1	4.88	5.67	8.07	8.72	6.66	5.08	4.26	2.6	1.53	56.25
Total Growing Degee Days from March 1		0	0	137	221	308	614	693	595	509	406	219	30	3732
Gross Pond Evap	Inch	1.4	2.53	3.44	4.1	4.76	6.78	7.32	5.59	4.27	3.58	2.18	1.29	47.24
Net Pond Evap	Inch	1.08	2.23	2.39	2.83	3.33	6.48	6.71	5.31	4.08	3.3	2.04	1.01	40.79
Berthoud	Avg. Temp ° F	28.7	36.95	41.85	48.41	54.41	71.53	74.2	68.94	63.77	55.59	44.24	25.75	51.2
Ref date as of 12/31/2016	Total Precip "	0.58	0.94	1.89	1.8	1.95	0.26	0.26	1.4	0.15	0.4	0.18	0.5	10.31
Site Type: Turf	Total Alfalfa ETr "	1.58	3.12	4.29	4.99	5.86	8.63	9.05	7.06	5.37	4.77	2.9	1.46	59.08
Total Growing Degee Days from March 1		0	0	121	197	271	611	697	580	465	354	173	16	3485
Gross Pond Evap	Inch	1.33	2.62	3.6	4.19	4.92	7.25	7.6	5.93	4.51	4.01	2.44	1.23	49.63
Net Pond Evap	Inch	0.92	1.96	2.28	2.93	3.56	7.07	7.42	4.95	4.41	3.73	2.31	0.88	42.42
Longmont West	Avg. Temp ° F	29.15	37.65	41.73	48.81	54.73	71.75	74.57	69.2	63.37	56.16	43.64	27.75	51.54
Ref date as of 12/31/2016	Total Precip "	0.42	0.51	1.72	1.77	2.1	0.6	0.09	0.79	0.3	0.37	0.15	0.25	9.07
Site Type: Turf	Total Alfalfa ETr "	1.49	2.81	3.6	4.59	5.42	7.59	8.09	6.38	4.9	4.33	2.35	1.47	53.02
Total Growing Degee Days from March 1		0	0	117	187	267	594	694	579	458	366	181	36	3479
Gross Pond Evap	Inch	1.25	2.36	3.02	3.86	4.55	6.38	6.8	5.36	4.12	3.64	1.97	1.23	44.54
Net Pond Evap	Inch	0.96	2	1.82	2.62	3.08	5.96	6.73	4.81	3.91	3.38	1.87	1.06	38.2
Fort Lupton	Avg. Temp ° F	28.03	37.27	42.01	48.41	54.61	71.57	74.83	70.05	64.65	57.19	45	26.66	51.69
Ref date as of 12/31/2016	Total Precip "	0.54	0.72	0.83	2.99	3.12	2.39	0.79	0.84	0.13	0.43	0.3	0.51	13.59
Site Type: Turf	Total Alfalfa ETr "	1.69	3.38	4.36	5.2	5.16	9.08	9.46	7.99	6.16	5.34	3.11	1.75	62.68
Total Growing Degee Days from March 1		0	0	135	200	280	604	689	607	485	385	199	23	3607
Gross Pond Evap	Inch	1.42	2.84	3.66	4.37	4.33	7.63	7.95	6.71	5.17	4.49	2.61	1.47	52.65
Net Pond Evap	Inch	1.04	2.34	3.08	2.28	2.15	5.95	7.39	6.12	5.08	4.18	2.4	1.11	43.12
Boulder NW	Avg. Temp ° F	31.71	39.04	40.9	47.5	54.07	71.41	74.14	69.3	63.42	57.06	45.71	29.72	52
Ref date as of 12/31/2016	Total Precip "	0.32	0.54	2.33	3.01	1.82	0.77	0.68	0.84	0.55	0.36	0.36	0.6	12.18
Site Type: Turf	Total Alfalfa ETr "	1.93	3.4	3.8	4.77	5.69	8.15	8.39	6.76	5.26	4.82	2.88	1.97	57.82
Total Growing Degee Days from March 1		0	0	111	182	265	593	681	576	449	366	188	43	3454
Gross Pond Evap	Inch	1.62	2.86	3.19	4.01	4.78	6.85	7.05	5.68	4.42	4.05	2.42	1.65	48.58
Net Pond Evap	Inch	1.4	2.48	1.56	1.9	3.51	6.31	6.57	5.09	4.03	3.8	2.17	1.23	40.05
Boulder East	Avg. Temp ° F	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Ref date as of 5/2/2010	Total Precip "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Site Type: Turf	Total Alfalfa ETr "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Total Growing Degee Days from March 1		0	0	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Gross Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Net Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Boulder Flatiron	Avg. Temp ° F	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Ref date as of 5/2/2010	Total Precip "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Site Type: Turf	Total Alfalfa ETr "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Total Growing Degee Days from March 1		0	0	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Gross Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Net Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Boulder SW	Avg. Temp ° F	34.93	41.58	42.76	48.44	54.27	71.2	73.39	69.03	63.96	58.48	47.63	31.01	53.06
Ref date as of 12/31/2016	Total Precip "	0.17	0.48	2.13	2.96	1.93	1.86	0.6	0.95	0.47	0.46	0.4	0.58	12.99
Site Type: Turf	Total Alfalfa ETr "	2.26	3.82	4.11	5.17	5.5	8.03	8.27	7.1	5.48	5.36	3.03	2.21	60.34
Total Growing Degee Days from March 1		0	0	98	160	241	599	653	571	436	336	165	38	3297
Gross Pond Evap	Inch	1.9	3.21	3.45	4.34	4.62	6.75	6.95	5.96	4.6	4.5	2.55	1.86	50.69
Net Pond Evap	Inch	1.78	2.87	1.96	2.27	3.27	5.44	6.53	5.3	4.27	4.18	2.27	1.45	41.59
Greeley04	Avg. Temp ° F	22.37	33.68	40.82	47.63	55.13	71.45	72.23	67.67	62.15	52.88	40.85	21.61	49.04
Ref date as of 12/3116/2016	Total Precip "	0.27	0.09	0.89	2.28	1.71	0.57	1.31	2.48	0.3	0.69	0.12	0.1	10.81
Site Type: Fully irrigated	Total Alfalfa ETr "	1.31	3.27	5.12	5.57	6.72	9.42	8.97	7.34	5.59	4.7	3.48	0.69	62.18
Total Growing Degee Days from March 1		0	0	132	203	291	587	655	568	457	357	175	2	3427
Gross Pond Evap	Inch	1.1	2.75	4.3	4.68	5.64	7.91	7.53	6.17	4.7	3.95	2.92	0.58	52.23
Net Pond Evap	Inch	0.91	2.68	3.68	3.08	4.45	7.51	6.62	4.43	4.49	3.47	2.84	0.51	44.67